Title: Fatal error in admin.php and class-wp-customize-manager.php
Last modified: August 31, 2016

---

# Fatal error in admin.php and class-wp-customize-manager.php

 *  [massterlist](https://wordpress.org/support/users/massterlist/)
 * (@massterlist)
 * [10 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-in-adminphp/)
 * Hello, my WordPress page was working as usual yesterday. I logged in to add two
   new users and give them administrative privileges, but did not alter any content.
   As of today, no users can log in to our dashboard.
 * Here are the error messages I see if I go to Dashboard, Themes, Widgets, or Menus:
 * Warning: require_once(/home3/mdeehan/public_html/massterlist.com/wp-admin/includes/
   theme.php): failed to open stream: No such file or directory in /home3/mdeehan/
   public_html/massterlist.com/wp-admin/includes/admin.php on line 67
 * Fatal error: require_once(): Failed opening required ‘/home3/mdeehan/public_html/
   massterlist.com/wp-admin/includes/theme.php’ (include_path=’.:/opt/php54/lib/
   php’) in /home3/mdeehan/public_html/massterlist.com/wp-admin/includes/admin.php
   on line 67
 * Here are the error messages I see if I go to Customize,
 * Warning: require_once(/home3/mdeehan/public_html/massterlist.com/wp-admin/includes/
   theme.php): failed to open stream: No such file or directory in /home3/mdeehan/
   public_html/massterlist.com/wp-includes/class-wp-customize-manager.php on line
   1763
 * Fatal error: require_once(): Failed opening required ‘/home3/mdeehan/public_html/
   massterlist.com/wp-admin/includes/theme.php’ (include_path=’.:/opt/php54/lib/
   php’) in /home3/mdeehan/public_html/massterlist.com/wp-includes/class-wp-customize-
   manager.php on line 1763
 * The website’s front end still appears fine. I am very new to WordPress and web
   design, so I do not know how to even begin to solve this problem without access
   to my dashboard.
 * Please let me know how to fix this! Thank you.

Viewing 1 replies (of 1 total)

 *  Moderator [t-p](https://wordpress.org/support/users/t-p/)
 * (@t-p)
 * [10 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-in-adminphp/#post-7125532)
 * Fatal error in the output generally indicates either: (1) your theme doesn’t 
   like your version of WordPress (2) you have a plugin that doesn’t like your version
   of WordPress (3) or you have an incomplete install/upgrade
 * So, try:
    – Flushing any caching plugins you might be running, as well as server
   and/or browser caches. Also, any op cache or content network cache, as well as
   Cloudflare, clear those caches. – deactivating ALL (yes all) plugins temporarily
   to see if this resolves the problem (plugin functions can interfere). If this
   works, re-activate them individually (one-by-one) to find the problematic plugin(
   s). – If you can’t get into your admin dashboard, try [resetting the plugins folder](http://codex.wordpress.org/FAQ_Troubleshooting#How_to_deactivate_all_plugins_when_not_able_to_access_the_administrative_menus.3F)
   by [FTP](http://codex.wordpress.org/FTP_Clients). Sometimes, an apparently inactive
   plugin can still cause problems. Also remember to deactivate any plugins in the
   mu-plugins folder (if you have created such folder). The easiest way is to rename
   that folder to mu-plugins-old. – switching to the unedited default Theme (Twenty
   Sixteen, etc.) for a moment using the WP dashboard to rule out any theme-specific
   issue (theme functions can interfere like plugins). If you don’t have access 
   to your admin area, use [FTP ](http://codex.wordpress.org/FTP_Clients), or your
   web-host’s cPanel or whatever file management application your host provides (
   no Dashboard access required). Navigate to /wp-content/themes/ and switch to 
   the default theme by renaming your current theme’s folder by adding “-old” to
   the end of the folder name. Alternately, you can remove other themes except the
   default theme. That will force your site to use it. – If all the above steps 
   do not resolve the issue, then try **MANUALLY** updating. Download a fresh copy
   of the WordPress .zip file to your computer, unzip it, and use that to copy up
   all files and folders **EXCEPT the wp-config.php file and the /wp-content/ directory.**
   You may need to delete the old wp-admin and wp-includes folders and files on 
   your server before uploading the new ones. Read the Manual Update directions 
   first. – **Backup: If you haven’t already done, always backup everything (including
   your database) before doing any actions, just in case something really goes wrong.**

Viewing 1 replies (of 1 total)

The topic ‘Fatal error in admin.php and class-wp-customize-manager.php’ is closed
to new replies.

## Tags

 * [admin.php](https://wordpress.org/support/topic-tag/admin-php/)
 * [fatal](https://wordpress.org/support/topic-tag/fatal/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 1 reply
 * 2 participants
 * Last reply from: [t-p](https://wordpress.org/support/users/t-p/)
 * Last activity: [10 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-in-adminphp/#post-7125532)
 * Status: not resolved

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